The aims of the project are (i) to identify and characterize the dynamic central nervous system adaptative mechanisms which govern the cerebral cortical response to somatic stimulation in normal subjects, and (ii) to determine their susceptability to manipulations and conditions known to be associated with orofacial sensory disorders in man. A team of investigators having extensive experience in somatosensory neurophysiology, pharmacology, human and animal psychophysics, and computer- aided neurobiological research have joined forces to study (i) the changes in somatosensory nervous system information processing associated with experimental modifications (long- and short-term) of sensory input consistent with those experienced by human subjects either in the course of everyday life or subsequent to traumatic injury or disease; (ii) the changes on somatosensory information processing accompanying clinical pain in man; and (iii) the capacity of normal human subjects and patients with orofacial sensory disorders to evaluate cutaneous motion on the skin. It is anticipated that this program of basic and clinical research will: (i) promote interactions and collaborations between investigators with different backgrounds; (ii) support core facilities designed to facilitate multidisciplinary research on somesthesia; and (iii) stimulate the exchange of ideas, instrumentation, know-how, and experimental materials.